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61.
BACKGROUND: Measurement of intraocular pressure by digital tension is a procedure that warrants study to determine if it could reliably yield pressure measurements for young children. METHODS: Sixty-two children (mean age, 3.8 years) served as subjects for the study. The examiner determined each child's digital tension in mmHg, classifying the measurement as soft to touch, medium to touch, or hard to touch. A masked examiner measured the intraocular pressure with a non-contact tonometer. RESULTS: Ninety-eight percent of the digital tension measurements yielded correct classification of the pressure when compared with non-contact tonometry results. The correlation for the digital tension determination of intraocular pressure with non-contact tonometry measurements was significant: 0.38 (p < 0.05) for O.D. and 0.39 (p < 0.05) for O.S. CONCLUSIONS: This study suggests use of digital tension as a reliable means of obtaining the intraocular pressure of young children. Digital tension tends to under-estimate the intraocular pressure when compared to non-contact tonometry readings.  相似文献   
62.
硝唑眯(Ⅰ)是六十年代发现的抗曼氏及埃及血吸虫药物。对日本血吸虫也有治疗作用,但毒副反应较大,应用受到限制。考虑到药物分子中氨基经酰化后毒性往往降低的一般规律,我们设计合成了一系列硝唑咪酰化物。  相似文献   
63.
We investigated whether the development of sympathetic innervation of the spleen is affected by lymphoid cells. Splenic noradrenaline (NA) levels of athymic nude mice (nu/nu) and normal thymus-bearing littermates (nu/+) were determined at different times during ontogeny. While no differences were detected at birth, higher splenic NA levels were found in 7-, 11-, and 21-day-old athymic mice. Thymus transplantation or thymocyte injection to newborn nude mice resulted in splenic NA levels comparable to those of normal nu/+ mice. Histochemical studies fully confirmed such differences. Taken together with previous studies, these results suggest that T lymphocytes or their products exert an inhibitory influence on sympathetic nerve fibers, thus leading to decreased NA content in the spleen. The data also illustrate the capacity of a nonneuronal cell in a peripheral organ to affect the process of autonomic innervation of this organ.  相似文献   
64.
65.
Inosine pranobex is a synthetic compound formed from the p-acetamido benzoate salt of N-N dimethylamino-2-propanol and inosine in a 3:1 molar ratio. It has been reported to exert antiviral and antitumour activities in vivo which are secondary to an immunomodulating effect, and early results suggest beneficial clinical effects in several diseases and infections including mucocutaneous Herpes simplex infections, subacute sclerosing panencephalitis, genital warts, influenza, zoster, and type B viral hepatitis, as well as in homosexual men with persistent generalised lymphadenopathy. However, many of the studies have been preliminary in nature and deficient in design or in the reporting of their results. One must therefore conclude that while inosine pranobex may prove to be a valuable and innovative therapy for a number of diseases and infections for which no satisfactory therapy exist, further long term well controlled studies in larger numbers of patients are required before definitive conclusions about the efficacy of inosine pranobex in these disorders will be possible.  相似文献   
66.
Radioimmunoimaging of fresh canine venous thrombi with a murine monoclonal antibody specific for human and dog fibrin has been reported. Successful imaging of canine deep venous thrombi 1, 3, and 5 days old at the time of antibody injection is reported. Images were positive in all dogs, and the uptake of fibrin-specific antibody was equivalent to that of fresh thrombi.  相似文献   
67.
H D Langtry  G J Mammen  E M Sorkin 《Drugs》1989,38(6):900-940
Urapidil is a postsynaptic alpha 1-adrenoceptor antagonist with a pharmacodynamic profile similar to prazosin. Unlike prazosin, however, urapidil also has some central activity which may explain the apparent improved tolerability of urapidil, including the absence of first-dose syncope. In clinical trials urapidil therapy resulted in significant reductions in blood pressure in patients with mild to severe essential hypertension, with little influence on heart rate. It is an effective antihypertensive when administered as monotherapy or in combination with beta-blockers and thiazide diuretics. In the few patients with cardiac dysfunction who have been studied to date, urapidil has improved myocardial oxygen consumption, systemic vascular resistance, left ventricular function, cardiac output and pulmonary capillary wedge pressure; however, further study is needed to assess the full therapeutic potential of urapidil in these patients. Urapidil has also been used successfully in the treatment of hypertensive emergencies, including eclampsia and pre-eclampsia, hypertensive crisis and hypertension occurring during general and cardiac surgery, rapidly lowering blood pressure without altering heart rate. Urapidil does not affect lipid or glucose metabolism, nor does it impair renal function. In addition, urapidil may be beneficial to patients with pulmonary hypertension, in whom it dilates pulmonary vascular beds to a greater extent than systemic vasculature, although therapeutic trials have not examined this effect. The most common adverse effects associated with urapidil therapy are dizziness, nausea, headache, fatigue and palpitations; however, these tend to be mild and transient and usually do not require discontinuation of treatment. Thus, urapidil offers a useful alternative to currently available drugs for the treatment of mild to severe hypertension, either as monotherapy or in combination with other antihypertensive drugs.  相似文献   
68.
LR Petersen  ; LS Doll 《Transfusion》1991,31(8):698-703
Transmission of human immunodeficiency virus type 1 (HIV-1) by homologous blood transfusion in the United States (US) is minimized by the deferral of potential donors who are at risk for HIV-1 infection and by the screening of all donations for HIV-1 antibody. HIV-1-seropositive donors at 20 blood centers were studied for information to be used in evaluating the safety of the US blood supply and making recommendations to increase that safety. From June 1988 to August 1989, 829 (0.04%) of 2,192,000 donors were found to be seropositive; 512 were interviewed. Of 388 seropositive men, 56 percent had had sex with men, 10 percent had used drugs intravenously, 8 percent had had sex with intravenous drug users, and 27 percent had no identified risk. Of 124 seropositive women, 58 percent had had sex with men at risk for HIV (81% of whom used drugs intravenously), 5 percent had used drugs intravenously, and 41 percent had no identified risk. Racial and ethnic minorities made up 68 percent of seropositive donors (black, 38%; Hispanic, 30%) and approximately 14 percent of all donors. The 157 persons with no identified risk had demographic characteristics and serologic test results for syphilis and hepatitis B that were more similar to those of HIV-1-seropositive donors with recognized risk than to those of seronegative donors. Three health care worker-blood donors (from an estimated 93,100 health care worker-donors) had infection that was probably acquired occupationally.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
69.
OBJECTIVES: To investigate the relationship of cardiovascular fitness (Vo(2)peak), neurologic deficits in balance and leg strength, and body composition to ambulatory function after stroke and to determine whether these relationships differ between those with milder versus more severe gait deficits. DESIGN: Cross-sectional correlation study. SETTING: Outpatient clinic of an academic medical center. PARTICIPANTS: Seventy-four people (43 men, 31 women; mean age +/- standard deviation, 64+/-10y) with chronic hemiparetic stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Thirty-foot (9.1-m) walk velocity, 6-minute walk distance, Vo(2)peak, Berg Balance Scale score, bilateral quadriceps eccentric torque, total and regional lean mass, and percentage of fat mass. RESULTS: Short-distance walking correlated significantly with cardiovascular fitness, balance, paretic leg strength, nonparetic leg strength, percentage of body fat, and paretic lean mass but not with nonparetic lean mass. Long-distance walking correlated significantly with cardiovascular fitness, balance, paretic leg strength, nonparetic leg strength, and paretic lean mass but not with percentage of body fat or nonparetic lean mass. Stepwise regression showed that cardiovascular fitness, balance, and paretic leg strength were independently associated with long-distance walking (r(2)=.60, P<.001). Variance in long-distance walking was largely explained by balance for those who walked more slowly (<.48m/s) for short distances (r(2)=.42, P<.001) and by cardiovascular fitness for those who walked more quickly (>.48m/s) for short distances (r(2)=.26, P=.003). CONCLUSIONS: Short-distance walking after stroke is related to balance, cardiovascular fitness, and paretic leg strength. Long-distance walking ability differs by gait deficit severity, with balance more important in those who walk more slowly and cardiovascular fitness playing a greater role in those who walk more quickly. Improved understanding of the factors that predict ambulatory function may assist the design of individualized rehabilitation strategies across the spectrum of gait deficit severity in those with hemiparetic stroke.  相似文献   
70.
目的:认知功能障碍是老年期抑郁症的可逆性症状,试验以认知功能研究为突破口,采用28通道的近红外光谱技术分析处于恢复过程中的老年期抑郁症患者在执行词语流畅性测验时前额叶的激活特点,探讨老年期抑郁症的发病机制。 方法:①分组:患者组为2006~03/12首都医科大学附属北京安定医院收治的12例处于恢复过程中的老年期抑郁症患者,入组时符合DSM-4有关重度和中度抑郁发作或复发的标准诊断,首次发病年龄≥60岁,均服用SSRIs类抗抑郁药物治疗。对照组为12例性别、年龄和教育程度与患者组相匹配的健康志愿者。所有受试者排除脑器质性病变:②试验方法:所有受试者接受近红外光谱测查,在28通道的CW5(TechEnInc.American)NIRS系统上完成。通过近红外光谱系统监测被试者在执行词语流畅性测验任务过程中,前额叶氧合血红蛋白和脱氧血红蛋白浓度的变化,从而反映前额叶认知任务相关的激活效应。采用组块设计的词语流畅性测验作为认知激活任务,任务范式包括词语重复任务和词语流畅性任务两种试验。 结果:24例受试者均进入结果分析。①在健康老年人和处于恢复过程中的老年期抑郁症患者,词语流畅性测验能够激活双侧前额叶.未发现半球单侧化激活效应。②处于恢复过程中的老年期抑郁症患者在词语流畅性测验任务过程中,左侧前额叶激活效应较对照组减弱。③尽管在健康老年人和处于恢复过程中的老年期抑郁症患者,近红外光谱显示了不同的激活模式,但词语流畅性测验的成绩不存在显著性的组间差异(P〉0.05)。 结论:处于恢复过程中的老年期抑郁症患者存在词语流畅性测验相关的功能性左侧前额叶功能减退,微血管功能失调和多巴胺系统异常也许在老年期抑郁症的病理生理学机制中起重要作用。  相似文献   
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